1. Field of the Invention
The present invention relates to a toner cartridge and a printer to which the toner cartridge is attached.
2. Description of the Related Art
Japanese Patent Publication (KOKAI) No. 63-231469 discloses a method of discharging toner from a toner cartridge into a developing unit, which in turn discharges the toner as a developer material to an electrostatic latent image bearing body of an electrophotographic printer.
The toner cartridge is attached to the developing unit of the printer. The toner cartridge has a shutter provided on the underside thereof. When the shutter is rotated, the toner falls from the toner cartridge into a hopper of the developing unit. Thus, the toner is held in the developer.
Recent printers used in the network place demands on large capacity toner cartridges. With conventional printers, the hopper of the developing unit is full of toner before and/or during printing, resulting in increased toner pressure in the hopper. The increased toner pressure causes poor print results.
The present invention was made in view of the aforementioned drawbacks of the conventional apparatus.
An object of the invention is to provide a toner cartridge that discharges a certain amount of toner for subsequent immediate printing operations when the toner cartridge is attached to the printer and then discharges fractions of the remaining toner in succession.
Another object of the invention is to provide a toner cartridge in which fractions of toner in the toner cartridge are discharged into a hopper when a toner-low state of the hopper is detected.
A toner cartridge is removably attached to a printer and discharges toner into the hopper of the printer. When the toner is discharged into the hopper for a first time after the toner cartridge has been attached to the printer, the toner cartridge discharges a certain amount of toner for immediate printing operations. Thereafter, a toner-discharging mechanism operates to discharge fractions of the toner held in the toner cartridge in succession into the hopper upon a toner-low signal. The printer has a controller and a detector. The detector detects an amount of toner remaining in the hopper. The controller controls the toner-discharging mechanism in accordance with the loner-low signal, i.e., detection signal of the detector such that the toner in the hopper is replenished in accordance with the amount of toner consumed. The controller controls the toner-discharging mechanism only when the toner remaining in the hopper is below a threshold.
A toner cartridge is removably attached to a printer and discharges toner into a toner hopper. The toner cartridge comprises a first toner chamber and a second toner chamber. When the toner is discharged into the toner hopper for a first time after the toner cartridge has been attached to the printer, the first toner chamber discharges all of the toner therein into the toner hopper. When the toner is discharged into the toner hopper after the first toner chamber has discharged the toner into the toner hopper, the second toner chamber discharges fractions of the toner held therein in succession into the toner hopper.
A toner cartridge has a toner chamber that holds toner therein. The toner cartridge is removably attached to a printer and discharging the toner into a toner hopper of the printer. The toner cartridge has a toner-discharging opening through which the toner is discharged from the toner chamber into the toner hopper. A toner-discharging mechanism is disposed to close the toner discharging-opening and the toner is discharged from the toner chamber through the toner-discharging opening into the toner hopper. The toner-discharging mechanism discharges fractions of the toner held in the toner chamber in succession into the toner hopper.
Another toner cartridge is used with a printer which has a toner hopper for receiving toner from the toner cartridge. The toner cartridge has a toner-discharging opening through which the toner is discharged into the toner hopper and a toner-discharging mechanism disposed to close the toner-discharging opening. The printer includes a controller that controls the toner-discharging mechanism to discharge the toner into the toner hopper only when an amount of toner remaining in the toner hopper is below a threshold value and a printing operation is being performed.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.